code: def _compute_logq0(sigma, order):
      key = (sigma, order)
      if key in _logq0_cache:
          return _logq0_cache[key]
  
      logq0 = compute_logq0_gnmax(sigma, order)
  
      _logq0_cache[key] = logq0  # Update the global variable.
      return logq0
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import math
  from absl import app
  import numpy
  import scipy
  import sympy
  import core
label_desc: Use image node_id 1 for calling a global function with example usage: _compute_logq0(sigma, order) and returns: logq0, _logq0_cache